固体酸催化剂上线性烷基苯生成反应动力学研究

Study on Reaction Kinetics of Linear Alkylbenzene Formation over Solid Acid Catalysts

在确定线性烷基苯反应生成动力学方程基础上 ,在消除外扩散影响前提下 ,用苯烯摩尔比为 1 0∶1的反应原料 ,在中孔分子筛负载杂多酸催化剂上进行苯与长链烯烃烷基化反应 ,采用气相色谱法分析反应组成 ,获得了不同反应温度、质量空速、催化剂粒度的烷基化反应试验数据。对模型进行参数估值 ,确定了线性烷基苯生成反应速率常数、扩散系数 ,以及反应活化能和扩散活化能参数 ,建立了考虑内扩散影响的线性烷基苯生成反应动力学模型 ,并开展模型评价、模型预测和反应规律研究。研究结果表明 ,线性烷基苯收率试验值和计算值的相关指数为 0 .9892 ,说明该模型具有较强的拟合试验数据能力 ,可信度较高。模型预测结果表明 ,线性烷基苯收率随着反应温度提高和原料与催化剂接触时间延长而不断提高 ,随催化剂粒径增大而降低。

Based on determined reaction kinetics equation for linear alkylbenzene formation, by using blending of benzene and long chain olefin as reaction material, after eliminating the affection of extra diffusion, over supported catalysts of mesoporous molecular sieve, the reaction was proceeded. The experimental data of forming alkylbenzene for different reaction temperature, WHSV and catalyst radius were gained. Then the parameters of linear alkylbenzene formation rate constant, diffusion coefficient, formation activation energy and the diffusion activation energy were obtained by simulating the experimental data of the alkylation in a liquid-solid reaction system. The reaction kinetics model of linear alkylbenzene formation, in which internal diffusion factors were considered, was established. The model evalution, model prediction and reaction law were researched. The results indicate that the established kinetics model exhibited a highly simulation precision; the model prediction indicated that alkylbenzene yield was increased with the increase of reaction temperature or the contact time extension between the material and catalyst and that the yield was decreased with the increase of catalyst radius.coefficient,f